Earth's deepest point thrives with bizarre bacteria

This handout photo, taken in 2009 by the unmanned submersible Nereus, shows the flat bottom of the Mariana Trench. (AP Photo/Tim Shank, Woods Hole Oceanographic Institution)

To the naked eye, life gets scarce the deeper into the ocean one goes. But both the ocean's surfaces and its floors are teeming with microscopic life, and the deepest point of all—the Challenger Deep canyon in the Mariana Trench nearly seven miles below sea level—is home to an abundance of an "unexp...